Game Genie Red/Blue
Warning, there is a possibility that these codes can possibly damge or destroy your game save files. Please use these codes at your own risk.

Fight Any Pokemon:
Enter the code, go to the grassy area west of Cerulean City. All Pokemon will be at Level 10.
Note One: This is the only area the code works!
Note Two: You might not fight the Pokemon right away, but it will eventuality show up!
Note Three: It's recommended that master ball's are used to catch all Pokemon
Note Four: If mew transforms before it is caught, it will be a ditto!

Easy Money: 996-11B-E6A
This code will change the value of Poke Balls to $990200. When you enter the store, turn the Game Geine off and buy some Poke Balls. Then exit, enter and turn the Game Geine back on. Now you sell Poke Balls for $495100!